|A symbol of the domain of ancestors|
Long ago, Devas had offsprings. Devas' attatchment to their offsprings once made them lax to their role as Brahma's helpers. Brahma took away self knowledge from the Devas upon noticing frequent occurances of this lax attitude. Devas prayed for self knowledge after realizing their loss. Brahma asked the Devas to seek it from their own offsprings who happyly taught it and blessed the Devas addressing them as "Putrakas or little ones". Devas acknowledged their teachers as Pitṛs or elders and gave them the status of Pitru-Devas. Pitru-devas, a class of devas, receive honors in ancestral worship rituals.
There are seven groups of Pitṛus (Vairajas, Agnishvattas, Barhishada, Somapas, Havishmanas, Ajyapas, and Sukalins) who are each assigned to different categories of beings. Seven great female Yogis emerged as mind born daughters from each of these seven categories of Pitru-Devas. Hari Vamsa text, a supplement to Mahabharata text, describes the influence of these Yoginis in the affairs of human beings. Their stories are fascinating. Acchoda, one among the seven, took birth as the mother of sage Veda Vyasa.